ニツケル板上に各種被覆劑を塗布したニッケル及びモネルメタル線を電極棒として熔着金屬ビードを造り、此の中に吸收された酸素を水素還元法に依る酸素定量裝置に依り定量分析を行つた結果次の如きことが判つた。
1,試料の形状は1mm以下でなければならない。
2.試料採取の場合には鐵鋼試料とは異り表面状況に依る實驗値の誤差は殆ど考える必要はない。
3.還元温度は約1,000℃で、3時間で完了する。
4.モネルメタル電極棒を使用すればニツケル電極棒を使用せしものより熔着部に吸收される酸素量は幾分少いが、未だ満足し得ない。

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The all welded ferry boat "Suva-Maru", which closed her life in 1932 after the service for 12 years, was demounted and observed the corrosivility of the welded line. As the results, any parts, where the painting kept its film, were found no trace of the corrosion along the welded line, but the welded parts, where exposed to the corrosive medium without painting, shown some corrosion. This corrosion was not due to the galvanic action between the deposited metal and mother plate but due to the yielding of the plate by the internal stress, produced during welding operations.
As to the corrosion of the welded stainless steel plate, the precipitation of carbide by the heat of welding increases the corrosivility of the plate. This precipitation of carbide depends upon the heating temperature and duration of welding and also carbon contents of the plate. So that, to prevent the increasing of corrosivility of the stainless steel, it is necessary to decrease the carbon content of the plate and welding duration. To shorten the welding duration, it is more preferable to adopt the electric arc welding, than the gas welding.

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